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Valve job - break in ?

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Old 04-15-2004, 03:48 PM
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Agro1
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Question Valve job - break in ?

My car should be re-born and back on the road pretty soon. It is having the following done:

RS tranny mounts
RS motor mounts
New powersteering belt
Lightweight flywheel and clutch
New plug wires
SAI cleaning
Hergesheimer modified (stock) exhaust - similar to Robin's RSR's
Valve job, new guides, etc...

Since the entire top end has pretty much been rebuilt, I was wondering if there will be any break-in considerations ? What do you guys think ?
Old 04-15-2004, 03:53 PM
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Randy M
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Empty your mailbox
Old 04-15-2004, 04:03 PM
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Agro1
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Done - thanks Randy...
Old 04-15-2004, 04:04 PM
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aam993
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Argo1,

I'm in the same boat - car is having valve job, carbon build up removal and RS clutch/LWF installation(thanks, Viperbob for the kit!).

I'm curious about RS engine/tranny mounts you mentioned. Since they're "RS" they should be better, but what exactly is good about them?
Since the engine just went to the machine shop I have time, I think, to ask to use RS mounts when engine will be put back, but wanted to better understand what are the benefits.

Thanks.
Old 04-15-2004, 06:45 PM
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Dr. No
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I recall way back when I had a valve job and big bore kit installed on my 914 the mechanic (Rich Bontempi) told me to break it in just like a new engine.
Old 04-15-2004, 06:58 PM
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Agro1
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Interesting, thanks Doc...
Old 04-15-2004, 07:40 PM
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ca993twin
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I wouldn't think there would be any break-in considerations on a top-end only rebuild. Dr No had a big-bore kit installed, which consists of new pistons, rings, cylinders, and wrist pins. That would be the reason for his mechanic advising him to break in his engine. IMHO.
Old 04-15-2004, 07:43 PM
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Agro1
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Yeah - I would think any rotating assembly changes, especially pistons and rings, would need some sort of break-in...
Old 04-15-2004, 09:42 PM
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Matt Vaughan
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Originally posted by small
Argo1,
I'm curious about RS engine/tranny mounts you mentioned. Since they're "RS" they should be better, but what exactly is good about them?
Since the engine just went to the machine shop I have time, I think, to ask to use RS mounts when engine will be put back, but wanted to better understand what are the benefits.

Thanks.
The RS tranny mount will make shifting more precise, as there will be less flex than the stock mount, but be prepared for noise! There is a LOT of gear noise. I personally think it sounds great, but it's not going to be for everyone. I have Supercups on my car and I can hear the gears over the 'cups. I would suggest sitting in a car, or race car for that matter since that's what it'll sound like, and determine if it's for you.

All in all though, a great upgrade coupled with the RS LWF and clutch!
Old 04-15-2004, 10:16 PM
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aam993
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Originally posted by Matt Vaughan
The RS tranny mount will make shifting more precise, as there will be less flex than the stock mount, but be prepared for noise! There is a LOT of gear noise. I personally think it sounds great, but it's not going to be for everyone. I have Supercups on my car and I can hear the gears over the 'cups. I would suggest sitting in a car, or race car for that matter since that's what it'll sound like, and determine if it's for you.

All in all though, a great upgrade coupled with the RS LWF and clutch!
Thanks, Matt!
I will check with the mechanic if my current mounts are worn out - in that case switching to RS mounts is no brainer.

Also, what is the best place for engine/tranny mounts?
Gert(carnewal.com) has RS engine mounts for $300. He doesn't have RS tranny mounts, though.
Old 04-16-2004, 12:21 AM
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Edward
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Agro1,

The phrase "top end rebuild" typically refers to pistons/rings/cylinders which may or may not include head work. If you mean only valves, seats, guides, and the like then there is not really a "break in" to do since these are not reciprocating parts or metal-to-metal that needs to mate properly....IF the valve job were done properly (that is, valve stems properly lapped to their seats and stems properly honed not reamed). That said, I'd personally feel like I'd still want to not redline for maybe 1K miles and keep the RPMs under 5K, after which I would rev liberally (after proper warm up, of course) and enjoy! Keep in mind that this latter point is an opinion and I have no factual basis for stating such an opinion other than gut feeling. Ask the one who did the valve work what is the appropriate protocol.

Edward
Old 04-16-2004, 12:54 AM
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Randy M '96 Silver 993
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Drive with the windows down. The Exhaust will sound sweet!!! I had it done and love.

As for the engine bits, I would ask Mark. He will give you all the info you need based on what he has done.
Old 04-16-2004, 03:57 AM
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Coleman
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Agro1, you better not get your car from Hergesheimer's before I get mine outta there.. mine's been there for like a month or two...... ;-)

Coleman
Old 04-16-2004, 11:04 AM
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Agro1
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Thanks Edward - I'll ask the guys doing it what they think...

Randy - so Mark split your exhaust as well ? How did the note change ? Throatier, louder ? How is it at idle ?

Coleman - Mine was parked (when I was there last week) right in front of yours. Good looking ride you have there man, love the wheels on the black car, looks pretty mean What are you having them do ? I spoke to Mark yesterday. Mine was supposed to be done this week, but 2 of the heads had to be sent out to have the valve seats replaced - soooooo - looks like it's gonna be end of next week. It's agonizing man, killing me....I guess I'll plan on picking it up mid July to be on the safe side
Old 04-16-2004, 12:31 PM
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Monique
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The RS mounts are indeed noisy.

LOTS of tranny noise.


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